Two-dimensional spectroscopy for the study of ion coulomb crystals.

Ion Coulomb crystals are currently establishing themselves as a highly controllable test bed for mesoscopic systems of statistical mechanics. The detailed experimental interrogation of the dynamics of these crystals, however, remains an experimental challenge. In this work, we show how to extend the concepts of multidimensional nonlinear spectroscopy to the study of the dynamics of ion Coulomb crystals. The scheme we present can be realized with state-of-the-art technology and gives direct access to the dynamics, revealing nonlinear couplings even in the presence of thermal excitations. We illustrate the advantages of our proposal showing how two-dimensional spectroscopy can be used to detect signatures of a structural phase transition of the ion crystal, as well as resonant energy exchange between modes. Furthermore, we demonstrate in these examples how different decoherence mechanisms can be identified

What do parents really want? Parents’ perceptions of their children’s schooling

International evidence confirms that parental involvement has substantial benefits for families and schools, as well as longterm economic benefits for developed and developing countries. To implement sound parental involvement two-way communication between home and school is essential. Schools worldwide tend to focus on communication from the school to the home, and afford parents fewer opportunities to express their perceptions of the quality of schooling. However, researcher-based, national and international surveys of parent opinion indicate that school endeavours to improve learner outcomes depend to a large extent on the data provided by parents. This article examines parents’ perceptions of their child’s schooling, gathered by means of an annual questionnaire administered in a public primary school in Gauteng, South Africa. A researcher-designed questionnaire administered annually over two consecutive years (2012 and 2013) was used to gauge parents’ opinions of school culture, home-school communication, classroom instruction and classroom organisation. The results indicate that parents were generally satisfied with all four areas. However, parents indicated concerns about reporting on an individual learner’s progress, academic achievement, and social and emotional wellbeing, as well as academic enrichment opportunities, and ways for parents to assist learning at home. In terms of classroom instruction and organisation, variations in parent responses emerged according to grade levels, and over the two-year reporting period. Recommendations were made, which could benefit other schools wishing to improve two-way communication with families through parent questionnaires.Keywords: classroom organisation; classroom teaching; family-school partnership; home-school communication; learner progress; parent surveys; quality of schoolin

Hazing in orientation programmes in boys-only secondary schools

Hazing, associated with initiation, aims at taking newcomers from novice status to a status of functional and acknowledged members of a new group. However, the process is often dangerous, injurious, and usually secretive. Hazing may occur as an unauthorised component of institutionally sanctioned orientation programmes commonly held for new students at educational institutions at the beginning of the academic year. This study focuses on the occurrence of hazing elements in orientation programmes (OP) for Grade 8 boys primarily run by Grade 12 learners in boys-only secondary schools in South Africa. A cross-sectional surveywas conducted by administering a researcher-designed questionnaire to a non-probabilistic sample of 296 Grade 12 learners enrolled at three boys-only secondary schools in Johannesburg. The computer assisted analysis strategy included frequency distributions, exploratory factor analysis, and analysis of variance. Findings indicated that respondents generally agreed with regard to the structure, aims, and behaviours common to orientation programmes. Respondents strongly disagreed about the occurrence of physical and sexual abuse and activities aimed at discomfort in the OP; however, respondents showed ambivalence about the occurrence of certain activities, which may deteriorate into hazing. Prior experience of an orientation programme when in Grade 8; length of enrolment in the school, and boarder status affected respondents’ perceptions of certain aspects of orientation programmes.Keywords: Boys-only secondary schools; gender theory; Grade 8 learners; Grade 12 learners; hazing; learner safety and wellbeing; masculinity; orientation programmes; psychological theories; survey researc

Syncope - A possible contributory mechanism

P

Defects of the Broad Ligament of the Uterus

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74780/1/j.1572-0241.1986.tb01505.x.pd

Multi-qubit gate with trapped ions for microwave and laser-based implementation

A proposal for a phase gate and a Mølmer–Sørensen gate in the dressed state basis is presented. In order to perform the multi-qubit interaction, a strong magnetic field gradient is required to couple the phonon-bus to the qubit states. The gate is performed using resonant microwave driving fields together with either a radio-frequency (RF) driving field, or additional detuned microwave driving fields. The gate is robust to ambient magnetic field fluctuations due to an applied resonant microwave driving field. Furthermore, the gate is robust to fluctuations in the microwave Rabi frequency and is decoupled from phonon dephasing due to a resonant RF or a detuned microwave driving field. This makes this new gate an attractive candidate for the implementation of high-fidelity microwave based multi-qubit gates. The proposal can also be realized in laser-based set-ups

Ground State Energy of the One-Component Charged Bose Gas

The model considered here is the `jellium' model in which there is a uniform, fixed background with charge density $-e\rho$ in a large volume $V$ and in which $N=\rho V$ particles of electric charge $+e$ and mass $m$ move --- the whole system being neutral. In 1961 Foldy used Bogolubov's 1947 method to investigate the ground state energy of this system for bosonic particles in the large $\rho$ limit. He found that the energy per particle is $-0.402 r_s^{-3/4} {me^4}/{\hbar^2}$ in this limit, where $r_s=(3/4\pi \rho)^{1/3}e^2m/\hbar^2$. Here we prove that this formula is correct, thereby validating, for the first time, at least one aspect of Bogolubov's pairing theory of the Bose gasComment: 38 pages latex. Typos corrected.Lemma 6.2 change